Insertion mutation

The answer is C. Production of a truncated protein indicates that a mutation has occurred, but this phenomenon may have arisen from a frameshift mutation (insertion or deletion) or by a nonsense mutation. The most likely possibility is a nonsense mutation because sequence analysis of the truncated protein showed that it had normal (wild-type) sequence. Insertion and deletion events often produce a stretch of garbled or abnormal protein sequence at the C-terminal end of the truncated protein arising from out-of-frame translation of the mRNA downstream of the mutation until a stop codon is encountered. 

Frameshift mutations. Insertions or deletions of genetic material that lead to a shift in the translation of the reading frame. The mutation usually leads to nonfunctional proteins. 

All other families 97 families Germ line mutations/ insertions in PRNP... 

Sequence alterations in viruses are common. Areas of high sequence variation may be interspersed between conserved domains. Higher frequencies of variation can be correlated with lower polymerase fidelity and may allow escape from antibody recognition and from antiviral drugs. Common mutations in viruses include point mutations, insertions, and deletions. Sequence diversity within a viral species may be so great that consensus sequences for molecular typing are difficult to find. 

Be familiar with DNA mutations (point mutations, insertions, deletions). 

Frameshift mutation Insertion or deletion of a number of nucleotides that are not divisible by three into a coding sequence, thereby causing an alteration in the reading frame of the entire sequence downstream of the mutation. 

Single-strand conformation polymorphism was originally described by Orita et al. [94] for the detection of point mutations. The idea of SSCP is to perform electrophoresis on a non-denaturing polyacrylamide gel using small PCR products after denaturation of the DNA. As the PCR product moves through the gel, it will regain a secondary structure that is sequence dependent (similar to RNA secondary structure). The mobility of the single-stranded PCR products depends on their secondary structure. Therefore, PCR products that possess sequence differences (mutations, insertions or deletions) will have different mobilities. 

A frameshift mutation inserts or deletes a base in the DNA sequence, which alters the mRNA codons after the mutation. 

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